The US Air Force Research Laboratory foresees dye-sensitised solar cells powering long-endurance unmanned air vehicles following scale-model ground and flight tests.

AFRL Researchers have found that solar cells made from carbon-based materials that use dyes and anti-reflection technology film have a higher specific power convergence efficiency. This means they are good at converting enough sunlight photons for electrical supply. These thin film solar cells can also be scaled up for a large-aircraft skin area.

"A few years ago the team mounted dye-sensitised solar cells on the wings of a toy airplane. The propeller was powered, but...the glass-based solar cells were...too heavy," says the laboratory. "Upon experimentation, they decided to use film battery technology, which worked and, in fact, enabled the plane to fly."

However, the AFRL expects that to integrate this technology into an operational UAV's wing will take a new five-year project. The University of Washington's Multidisciplinary University Research Initiative project team is working on the cells for the AFRL that use a flexible film and a thin glass coating that has a transparent conductive electrodes. The team is also investigating "bioinspired dyes" that aid even more efficient photon conversion.

Source: Flight International